Electrical fixture



Patented Mar. 2, 1954 ELECTRICAL FIXTURE John B. Cataldo, Bernardsville,N. J., assignor to John B. Pierce Foundation, New York, N. Y., acorporation of New York Application April 16, 1952, Serial No. 282,615

1 Claim.

This invention relates to electrical fixtures and more particularly tofixtures adapted to be quickly and simply inserted in series with atleast one electrical conductor of an electrical conduit.

Electrical fixtures, such for example as switches and like devices, aregenerally connected in electrical circuits by attaching electricalconductors to binding posts, lugs or other terminal means. Considerabletime and skill may be required if satisfactory connections are to bemade, and in many cases even perfectly executed connections aremechanically insecure. The development of electrical wiring systemsutilizing fiat, semi-rigid electrical strip conduits comprising, forexample, a pair of heavy conductors embedded in a unitary insulatingstrip has created a need for new fixture designs and this invention isconcerned with the design of fixtures which overcome many of thedisadvantages of conventional fixtures used in conventional wiringsystems.

Accordingly, it is an object of this invention to provide an improvedelectrical fixture which is both safe in its design and eificient in itsmounting and installation characteristics.

It is another object of the invention to provide an electrical fixturewhich is particularly adaptable for use with semi-rigid strip wiringconduits including heavy electrical conductors held in fixed relativepositions by means of moulded insulating material.

It is a further object of the invention to provide an improvedelectrical fixture which may be quickly and simply attached toelectrical conductors and in which the possibility of the conductorsbeing short circuited is obviated.

These and other objects and features of the invention may be obtained byproviding an electrical fixture including a housing portion formed withinternal recesses for receiving a strip conduit, and barrier means forinsuring the continued separation of the electrical conductors withinthe fixture. The housing parts are preferably so arranged that the unitmay not be assembled if the electrical conductors are improperlypositioned within the housing. Suitable recesses are formed in thehousing to receive connecting members for joining the electricalconductors with the terminal means of the fixture. These connectingmembers preferably comprise spring clip links which grip both theconductors and the terminal means, the gripping action being enhanced bythe compressing action of the recesses formed in the housing. In apreferred embodiment of the invention channel means are provided in thehousing for receiving an unsevered electrical conductor of the conduitwhich is permitted to pass directly through the fixture in such a waythat the electrical conduit may itself carry tensile stresses whichwould ordinarily be borne exclusively by the terminal means of thefixture.

The invention may be better understood by reference to the accompanyingdrawing in which Fig. 1 is a top view of an electrical fixture formed inaccordance with the present invention and shown attached to anelectrical conduit;

.Fig. 2 is a side view partly in section of the fixture shown in Fig. 1;

Fig. 3 is a bottom view of the fixture with the bottom cover memberremoved;

Fig. 4 is a View in transverse section taken on the line 44 of Fig. 2looking in the direction of the arrows;

Fig. 5 is a View in transverse section taken on the line 5-5 of Fig. 2looking in the direction of the arrows; and

Fig. 6 is a plan View of the inside surface of the bottom cover member.

For purposes of illustration the invention is shown as embodied in anelectrical switch assembly identified generally by the numeral 9. Theassembly includes a unitary, molded housa ing shell H], which may beformed of plastic or other insulating material, having an enlargedcentral portion H formed with a slot !2 in its outer surface.

Received within the central portion I! is an electrical device orelement adapted to be connected in series with an electrical conductorand which may comprise, for example, a single-pole, double-throw switchunit I3 having an operating lever M which projects out of the slot I2 inthe housing. Such switch devices are well known and any one of numerousconventional designs may be utilized. The electrical device l3 may besecured within the housing It) by means, for example, of mounting screws15 and supporting lugs I6 disposed at opposite ends of the unit. Thedevice !3 is also provided with terminal means comprising a pair ofblade members Ila and Nb formed of electrical conducting material andprojecting outwardly from its respective ends and in the same plane.

The housing It! is symmetrically formed with side portions I84: and itb,and the underside of the housing is provided with wall means andabutments defining a longitudinal channel having end portions Mia andiilb. The channel is adapted to receive a strip conduit 20 whichcomprises a pair of parallel, coplanar heavy electrical conductors 2!,22, such as No. 10 or 12 wire, for example, embedded in a unitaryinsulating covering including rounded edges 23 joined by a central webportion 26. Such conduit is semi-rigid so that it may be made, ifdesired, to carry fixtures having no other means of support but isneverthe less capable of being bent to comply with the contours of thesurfaces on which it is mounted. In most cases the conduit is mounted bymeans of fasteners penetrating the web portion 24 and entering amounting surface such, for example, as a wall or base board.

Within the confines oi the housing ID the insulation iststripped fromthe conductors 2| and 22. Further, the conductor 22 is severed so as toprovide a pair of free end or conductor portions 22a and 221) which arepreferably aligned and longitudinally spaced apart by removal of a pieceof the conductor. The conductor portions 22a and 22b are adapted to .beconnected electrically to the terminals I10, and 11b of the electricaldevice I3. To this end, the housing III is formed with a pair ofrecesses 25 adjacent the respective conductor portions 22a and 22b.Joining the terminal blade Ila and the conductor end 22a, as best seenin Fig, is an electrically conducting connector or clip member 26ahaving a rounded bignt 21 adapted to surround the conductor 22aandjhaving a pairc'f outwardly diverging leg portions 28, the free endsof which are in'turned at 29 to form a reentrant channel for receivingthe terminal blade [1a.

The clip 26a, when pressed into the channels 25, vslidably engages theblade Ila in a tight clamping fit which also causes the clip to bindtightly at its bight .21 about the conductor portion22a.

The conductor end 221) is similarly joined to the terminal blade 1 1b atthe other side of the device 13 by a-clip 262) so that the deviceis-connected in series with the conductor 22.

The electrical device 13 is preferably provided with a fiat insulatingsurface I 3aonits backside which may be utilized as one of the surfacesdefining the conduit-receiving channel within the housing [0 andadjacent which the bared conductors 2|, and 22a and b of the conduit maybe disposed. The underside of the housing is adapted to be covered by aclosure or back portion 30 carrying on its innertsurface, wall meansdefining a first guide channel or slot 3| for receiving the throughconductor 2| of the conduit 2|], and a pair of aligned channels or slots32a and 32b, divided by a barrier portion 33, for receivingtherespective conductor portions 22a and 22b-of the severedconductor 22.It will be understood that the construction of the channels insures thatthe conductor 22 is properly severed and separated at its severedends,for the reason that the barrier 33 will prevent the proper seating ofthe closure portion 30 in the housing It unless an adequate gap isprovided between the conductor ends 22a and 22b. When the closureportion 35, is properly seated in the housing the wall means definingthe channels or slots 3| and 32a and b will be disposed close to theback surface ,l3a of the electrical device [-3, thereby to efiectivelyconfine the baredelectrical conductors on .all sides. The closureportion 30 may be attached to the housing by means of screwsreceived inholes 34.

The fixture may be mounted on a supporting surface by means ofmounting-screws received incountersunk bores 35' formed in the ends ofthe housing, the bores 35 being so positioned that the mountingscrewspenetrate the web portion 24 of the electrical conduit 20, at best seenin -Fig. 3.

It will be understood that the penetration of the web .20 by themounting screws 3.5 tends to prevent the insulating portion of theconduit 20 from being pulled or stripped backwardly on the conductors.

Further, if tension is applied to the conduit :20 externally of thefixture, the tensile load will be carried both by the .unseveredelectrical conductor 2.! and-by the insulating portion which is attachedthe housing need not necessarily be 4 to the housing l0 so that it isvirtually impossible rior the severed conductor 22 to becomeaccidentally disconnected from the :electric *device l3.

The particular form of the invention herein described and illustrated inthe accompanying drawings is presented merely as an example of how theinvention may be applied. Numerous modifications inthe-details of theswitch assembly may .be made without departing from the scope of theinvention. Thus, for example, various types of electrical devices may beutilized. Also, the unsevered conductor which passes through completelybared of insulation, particularly if it is not to be connectedelectrically within the fixture. Qther forms, embodiments andapplications of the in- ,vention coming within the proper .scope of theappended claim will, therefore. suggest themselves to those skilled inthe art.

I claim:

In an electrical fixture for use in conjunction with an electrical stripconduit comprising .coplanar laterally spaced-apart parallel electricalconductors embedded in a unitary insulating portion, the conductors ofthe conduit being stripped of insulation for a length to be receivedwithin the fixture andat least one of the stripped conductors beingsevered by removal oia piece thereof to provide aligned longitudinallyspaced-apart free .end portions of the conductor, a housing, wall meansin thehousing defining a channel for receiving the stripped conduit inexcess of the length stripped of insulation, said unsevered-conductorpassing through the housing without being bent, an electrical devicemounted .in the housing and having first and second electrical terminalsand a flat insulating surface bounding at least a portion of the channelfor the-conduit, wall means defining recesses in "the vicinity of thesaid terminals, a pair of electrically conducting clip members adaptedto surround respectively the aligned free ends of the severed conductorand to be received in the recesses to engage the terminals of theelectricaldevice to connect the device in series with thesevered-electrical conductor, and a closure portion adapted to beattached to the housing to close the conduit-receiving channel in thehousing, said :clo sure portion having walls defining channels .for

receiving the respective stripped electrical conductors of theconduitwithin the housingtohold the-conductors in parallelism and to preventlateral movement of the conductors, said wall means alsodefining abarrier portion adapted to bedisposed between the aligned .free ends ofthe severed conductor, said wall means, when therclosure portion is :inposition, being disposed close to the said flat surface of theelectrical device and cooperating therewith to confine the electricalconductors of the conduit, whereby the closure portion :and housing maynot be assembled in the absence of proper positioning o! the electricalconductors within the housing, and. whereby the electrical fixture maybe attached to the strip conduit without bending either the severed oriunsevered conductors.

JOHN B. CA'I ALDO.

References Cited in the ills of this patent UNITED "STATES PATENTS IName Date, .Zielov "a..-

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